Slow-acting device



W. P. NEUBERT.

SLOW ACTING DEVICE.

APPLICATION man MAY 14. me.

I' Patented July 22, 191%).

ill M UNITED STATES. Parana ernten,

WALTER P. NEUBERT, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, 0F SWISSVALE, PENNSYLVANIA, A CORPORATION- 0F PENNSYLVANIA.

SLOW-ACTING DEVICE.

Specification of Letters Patent. Patented July 22, 1919,

Application led Hay 14, 1918. Serial No. 234,565.

To all whom t may concern.' l

Be it known that I, WALTER P. NEUBERT,

a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Slow-Acting Devices, of which the following4 is a specification.

My invention relates to lslow-acting devices, and particularly to devices of this character `which depend for their action on the Aflow of a fluid through a restricted oriice. 4Devices embodying my invention are well adapted for use in connection with apparatus for the control of railway switches and signals, although they are not limited to this particular field.

I will describe one form of slow-acting device embodying my invention and will then point` out the novel features thereof in claim In the accompanying drawings, Figure 1 is a view lshowing in vertical section one form of device "embodying my invention.

yFig- 2 is a view, partly 1n elevation and partly sectioned, taken at right angles to Fig. 1 and showing the upper portion of the device shown in Fig. 1.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1, the device in the form here shown comprises a hollow cylindrical member 1, the lower inner rim of which is threaded to receive a cap 2. The inside of the rim at the bottom of cap 2 is likewise threaded toreceive a second cap 3. Passing through the cap 2 at one side thereof is an opening 2a. The cylindrical member 1, the opening 2a in cap 2, and the cap 3,. constitute an outer Huid container which I will designate collectively the reference character O. Located inside of this container isa cylindrical memberl 4 mounted Iin .cap 2 and comprising, with this cap, a second or inner fluid container designated collectively as I. The upper end of member 4 is -located below the top of the outer container. O, and this member 4 is not provided with a cap at its upper end. Hence it follows that the two fluid containers com` tached a rod '6 extending upwardly and co# acting with any suitable apparatus such as that which will be described hereinafter. The plunger is of such size as to be movable within the container I with a small amount of clearance. The inner and outer containers are Ifilled, to about the level indicated, with a fluid 7 having sulicient specifc gravity to float the plunger 5; this fluid is preferably mercury.

It will now be apparent that when the plunger 5 is forced downwardly from the position in which it is shown, some of the fluid in the inner container, that is, some of the fluid between the plunger 5 and the member 4, will be driven upwardly and will spill over into the outer container O. The downward movement of the plunger is not retarded to an appreciable amount because of the large opening between the two containers at the top of the member 4f. When the pressure on the plunger is removed, the Huid which was transferredfrom the inner to the outer container returns through the opening 2", and in so. doing it raises the plunger to its initial position, that is, to the position in which it is shown in the drawing. This return or upward movement is comparatively slow, however, because of the comparatively small area of the opening 2b, and Iof course the time repuired for the complete return movement o the plunger to be accomplished will vary with variationsin the area of this openin 4 A The effective area ci opening 2b is controlled by a conical valve 8 which may be movedinto and out lof the opening, so that the effective area is Icomlparatively large when the valveis all the way out, and comparatively small or zero when the valve is in as far as it will go. This valve is, attached to a flexible diaphragm 9 which is supported between the two caps 2 and 3, and

. owing to its location it constitutes the lower constantly biased to such position that the valve'S is entirely out of opening 2", that is, to'- such osition that the effective area of the opening is maximum. To raise the diaphragm,- and consequently the valve 8, I provide a screw 10 which passes through a threaded hole in the c ap 3 and which abuts against the end of a screw 1'1 carried by the diaphragm. It will be clear that by turning the screw 10 in one direction or the other, the diaphragm 9 may be raised against the action of the fluid .pressure or may be allowed to fall due -to the action of the fluid pressure, and so the 'effective area of the opening 2" may be varied by ininitely small increments between the two extreme values.

One important feat-ure of my present invention, then, is the provision of means for adjusting the effective area of the opening 2b from the'outside of the outer fluid container, so that this adjustment can be made without removing any part of the device. Another important feature is the provision of means for -varying the eifective area of this opening by infinitely small increments.

In a slow-'acting device df this character it is of course desirable -that the force tending to lift the plunger 5 :be as great as practicable, and that this force `be substantially as great when the plunger is` near the upper end of its lstroke as when it is at the lower end. To accomplish this result, the level of the fluid must xbe kept high, so as to provide as great a head as possible. In order' to do this with the minimum amount of fluid, I construct thedevice in such manner that the horizontal area of the space between the plunger and the inner container is as small as practicable, and that likewise the hori. zontal area of the space between Ithe inner and'outer containers is as small as practicable except near the level of the fluid where the outer container is widened out as shown to provide an overilow chamber. This over- :llow chamber is of such size' that the level of the fluid therein is substantially the same when the plunger is at the to-p of its stroke as when the plunger is at the bottom of its stroke, hence the head of the fluid is substantially the same for all positions of the plunger and is comparatively great for a comparatively small quantity of fluid.

The upper end of the plunger 5 is prefera'bly -provided with an umbrella-shaped top 5 to deflect the fluid on the down stroke of the plunger. This prevents the fluid from passing up between the rod 6 and the housing around this rod, and squeezing out at the top of the device.

The plunger' may be actuated by any suitable means, and may in turn be employed to control any suitablemeans. As here shown, the upper end of the rod 6 coacts with a segment 12 which is attached to a shaft 13 of an interlocking machine such as is commonly employed for the control of railway switches and signals. Attached to the rod 6 is a yoke 14 which straddles the segment 12 as shown in Fig. 1. When the shaft 13 and segment 12 are in their middle osition as shown in Fig. 2, the plunger 5 1s at the top of its stroke. If now the shaft and segment are turned in clockwise direction as viewed in Fig. 2, the lug 12a on segment 12 will depress the plunger 5; the segment may then be returned toward its middle position but will be stopped by the engagement of the shoulder 12b and the upper arm of yoke 14. The lsegment is locked in this mid-stroke position for the period of time required for the plunger to rise to its upper position, whereupon the segment is released and may then be returned to its middle position. v l

Although I have herein shown and described only one form of slow-acting device embodying my invention, it is understood that variou-s changes and modifications may be made therein within the scope of the appended claims without departing from the lspirit and scope of my invention.

Having thus described my invention, what l I claim is:

1. A slow-acting device comprising outer and inner fluid containers, a plunger'within the inner container, fluid in said containers of suliicient specific gravity to float said plunger, said containers communicating with each other above the highest level of the fluid in the outer container, an opening through the inner container below the lowest level of the fluid in the outer container, a valve coperating with said opening to vary the effective area thereof, and means extending through the outer container for moving said valve.

2. A slow-acting device comprising outer and inner fluid containers, a plunger within thelinner container, fluid in said containers of sufficient specific gravity to float said plunger, said containers communicating with each other above the highest level of the fluid in the outer container, an opening through the inner container below the lowest level of the fluid in theouter container, a valve coperating with said opening to vary the effective area thereof, and means for moving said valve from outside of said outer container.

3. A slow-acting device comprising outer and inner fluid containers, a plunger within the inner container, fluid in said containers of sufficient specific gravity to float said plunger, said containers communicating with each other above the highest level of the Huid in the outer container, an opening through the inner container below the lowest level of the fluid in the outer container, and means located partly within said outer container and extending to the outside thereof for varying the eiective area of said openmg.

4. A slow-acting device comprising outer and inner Huidt containers, a plunger within the inner container, fluid in said containers of suiicient specific gravity to float said plunger, said containers communicating with eachother above the highest level of the fluid inthe outer container, an opening through the inner container below the lowest level ofthe fluid in the outer container, a iexible diaphragm in said outer container subject to the pressure of said Huid on one side but not on the other, a valve carried by said diaphragm and coperating with said openingto vary the effective area of the latter, and means extending through said outer container for moving sald diaphragm in opposition to the pressure of said Huid thereon.

5. A slow-acting device comprising outer and inner fluid containers, a plunger within the inner container, fluid in said containers of suicient specific gravity to oat said plunger, said containers communicating with each other .above the highest level of the `fluid in the outer container, an opening through the inner container below the lowest level of the fluid in theouter-container, a iexible diaphragm in said outer container A subject to the pressure of said Huid on one 'side but not on the other, a valve carried by.

said 'diaphragm and coperatingwith said opening to vary the effective area of the latter, and a screw passing through athreaded hole in said outer container to move said 'with each other by two openings located respectively above and below the level of the fluid in the outer container, the horizontal area of the space between the plunger and the inner container being comparatively small, and the horizontal area of the space between the two containers being comparatively small throughout the greater part of the vertical height of the fluid in the outer container but comparatively large near the level of the fluid in the outer container.

7. A slow-acting device comprising inner and outer fluid containers,a plunger within the inner container, uid in saidl containers of suicient speciicy gravity to oat said plunger, said containers communicating with each other by two openings located respectively above and below the level of the Huid in the outer container, said' lunger being provided with a shield to eilect fluid which is forced upwardly when the plunger is forced downwardly.

In testimony whereof I affix my signature in presence of two witnesses.

WALTER P. NEUBERT.

Witnesses:

A. HERMAN WEGNER, FAY GLASGOW. 

